文献类型：期刊文献

英文题名：Intracellular expression of Vitreoscilla hemoglobin improves S-adenosylmethionine production in a recombinant Pichia pastoris

作者：Chen, Huaxin[1]; Chu, Ju[1,2]; Zhang, Siliang[1]; Zhuang, Yingping[1]; Qian, Jiangchao[1]; Wang, Yonghong[1]; Hu, Xiaoqing[1]

机构：[1] State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; [2] East China University of Science and Technology, 130 Meilong Rd., Shanghai, China

年份：2007

卷号：74

期号：6

起止页码：1205

外文期刊名：Applied Microbiology and Biotechnology

收录：EI(收录号：20071910587472)

语种：英文

外文关键词：Bacteria - Biosynthesis - Cell growth - Concentration (process) - Hemoglobin - Methanol

摘要：To develop an efficient way to produce S-adenosylmethionine (SAM), methionine adenosyltransferase gene (mat) from Streptomyces spectabilis and Vitreoscilla hemoglobin gene (vgb) were coexpressed intracellularly in Pichia pastoris, both under control of methanol-inducible promoter. Expression of mat in P. pastoris resulted in about 27 times higher specific activity of methionine adenosyltransferase (SMAT) and about 19 times higher SAM production relative to their respective control, suggesting that overexpression of mat could be used as an efficient method for constructing SAM-accumulating strain. Under induction concentration of 0.8 and 2.4% methanol, coexpression of vgb improved, though to different extent, cell growth, SAM production, and respiratory rate. However, the effects of VHb on SAM content (specific yield of SAM production) and SMAT seemed to be methanol concentration-dependent. When cells were induced with 0.8% methanol, no significant effects of VHb expression on SAM content and specific SMAT could be detected. When the cells were induced with 2.4% methanol, vgb expression increased SAM content significantly and depressed SMAT remarkably. We suggested that under our experimental scheme, the presence of VHb might improve ATP synthesis rate and thus improve cell growth and SAM production in the recombinant P. pastoris. ? 2007 Springer-Verlag.